I've had a chance to look at this again, and have what seems to be a workable solution: however since the fix involves checking to see whether a define is set or not and then setting a guard macro appropriately - in order to suppress warnings from Boost.Config defined macros - I've had to include boost/config.hpp in workaround.hpp. Is this acceptable, or should these guard macros be defined in Boost.Config instead? The latter seems more fragile to me, but I could just be being over cautious. I also can't guarantee that this will suppress 100% of the -Wundef warnings, but I think I've quashed about 95% of them. The proposed patch is at the end, any comments anyone? John. Index: C:/data/boost/boost/trunk/boost/detail/workaround.hpp =================================================================== --- C:/data/boost/boost/trunk/boost/detail/workaround.hpp (revision 39175) +++ C:/data/boost/boost/trunk/boost/detail/workaround.hpp (working copy) @@ -38,8 +38,136 @@ # ifndef BOOST_STRICT_CONFIG +#include <boost/config.hpp> + +#ifndef __BORLANDC__ +#define __BORLANDC___WORKAROUND_GUARD 1 +#else +#define __BORLANDC___WORKAROUND_GUARD 0 +#endif +#ifndef __MSC_VER +#define __MSC_VER_WORKAROUND_GUARD 1 +#else +#define __MSC_VER_WORKAROUND_GUARD 0 +#endif +#ifndef _MSC_FULL_VER +#define _MSC_FULL_VER_WORKAROUND_GUARD 1 +#else +#define _MSC_FULL_VER_WORKAROUND_GUARD 0 +#endif +#ifndef BOOST_MSVC +#define BOOST_MSVC_WORKAROUND_GUARD 1 +#else +#define BOOST_MSVC_WORKAROUND_GUARD 0 +#endif +#ifndef __GNUC__ +#define __GNUC___WORKAROUND_GUARD 1 +#else +#define __GNUC___WORKAROUND_GUARD 0 +#endif +#ifndef __GNUC_MINOR__ +#define __GNUC_MINOR___WORKAROUND_GUARD 1 +#else +#define __GNUC_MINOR___WORKAROUND_GUARD 0 +#endif +#ifndef __GNUC_PATCHLEVEL__ +#define __GNUC_PATCHLEVEL___WORKAROUND_GUARD 1 +#else +#define __GNUC_PATCHLEVEL___WORKAROUND_GUARD 0 +#endif +#ifndef __IBMCPP__ +#define __IBMCPP___WORKAROUND_GUARD 1 +#else +#define __IBMCPP___WORKAROUND_GUARD 0 +#endif +#ifndef __SUNPRO_CC +#define __SUNPRO_CC_WORKAROUND_GUARD 1 +#else +#define __SUNPRO_CC_WORKAROUND_GUARD 0 +#endif +#ifndef __DECCXX_VER +#define __DECCXX_VER_WORKAROUND_GUARD 1 +#else +#define __DECCXX_VER_WORKAROUND_GUARD 0 +#endif +#ifndef __MWERKS__ +#define __MWERKS___WORKAROUND_GUARD 1 +#else +#define __MWERKS___WORKAROUND_GUARD 0 +#endif +#ifndef __EDG_VERSION__ +#define __EDG_VERSION___WORKAROUND_GUARD 1 +#else +#define __EDG_VERSION___WORKAROUND_GUARD 0 +#endif +#ifndef __HP_aCC +#define __HP_aCC_WORKAROUND_GUARD 1 +#else +#define __HP_aCC_WORKAROUND_GUARD 0 +#endif +#ifndef _CRAYC +#define _CRAYC_WORKAROUND_GUARD 1 +#else +#define _CRAYC_WORKAROUND_GUARD 0 +#endif +#ifndef __DMC__ +#define __DMC___WORKAROUND_GUARD 1 +#else +#define __DMC___WORKAROUND_GUARD 0 +#endif +#ifndef MPW_CPLUS +#define MPW_CPLUS_WORKAROUND_GUARD 1 +#else +#define MPW_CPLUS_WORKAROUND_GUARD 0 +#endif + +#ifndef _RWSTD_VER +#define _RWSTD_VER_WORKAROUND_GUARD 1 +#else +#define _RWSTD_VER_WORKAROUND_GUARD 0 +#endif +#ifndef _GLIBCXX_USE_C99_FP_MACROS_DYNAMIC +#define _GLIBCXX_USE_C99_FP_MACROS_DYNAMIC_WORKAROUND_GUARD 1 +#else +#define _GLIBCXX_USE_C99_FP_MACROS_DYNAMIC_WORKAROUND_GUARD 0 +#endif +#ifndef __SGI_STL_PORT +#define __SGI_STL_PORT_WORKAROUND_GUARD 1 +#else +#define __SGI_STL_PORT_WORKAROUND_GUARD 0 +#endif +#ifndef _STLPORT_VERSION +#define _STLPORT_VERSION_WORKAROUND_GUARD 1 +#else +#define _STLPORT_VERSION_WORKAROUND_GUARD 0 +#endif + +#ifndef BOOST_INTEL_CXX_VERSION +#define BOOST_INTEL_CXX_VERSION_WORKAROUND_GUARD 1 +#else +#define BOOST_INTEL_CXX_VERSION_WORKAROUND_GUARD 0 +#endif +#ifndef BOOST_INTEL_WIN +#define BOOST_INTEL_WIN_WORKAROUND_GUARD 1 +#else +#define BOOST_INTEL_WIN_WORKAROUND_GUARD 0 +#endif +#ifndef BOOST_DINKUMWARE_STDLIB +#define BOOST_DINKUMWARE_STDLIB_WORKAROUND_GUARD 1 +#else +#define BOOST_DINKUMWARE_STDLIB_WORKAROUND_GUARD 0 +#endif +#ifndef BOOST_INTEL +#define BOOST_INTEL_WORKAROUND_GUARD 1 +#else +#define BOOST_INTEL_WORKAROUND_GUARD 0 +#endif +// Always define to zero, if it's used it'll be defined my MPL: +#define BOOST_MPL_CFG_GCC_WORKAROUND_GUARD 0 + # define BOOST_WORKAROUND(symbol, test) \ - ((symbol != 0) && (1 % (( (symbol test) ) + 1))) + ((symbol ## _WORKAROUND_GUARD + 0 == 0) && \ + (symbol != 0) && (1 % (( (symbol test) ) + 1))) // ^ ^ ^ ^ // The extra level of parenthesis nesting above, along with the // BOOST_OPEN_PAREN indirection below, is required to satisfy the